I have aquired an amplifier with one working chanel, and one channel that seems to stick to one power supply rail (DC voltage). It uses an STK461 chip amp and the number and structure of the components inside looks relatively simple. Whilst i can aquire a replacement chip i am wondering what other tests i should run or common faults to look for before i go buying a chip that i don't need. Any pointers or links to tutorials etc?

There's very little externally to go wrong with these chips. The only thing I can think of is to check that the DC isn't coming from a preamp stage (eg a missing rail to one of the opamps). This is unlikely though.

It is likely the chip is damaged possibly due to a short on the channel. Replacing the chip is the most likely fix.

The chip is damaged,I have had simmilar experiences with STK series IC's ~ STK 459 and 4141 ,these chips are very sensitive to shorts in the output.But I doubt if you will be able to obtain a genuine STK 461 as these became obsolete arnd 10 years back...

Just an advice, when you install those kind of chip, place an alligator clip with a wire at each pin ,hook up to the ground .Just move the clip from pin to pin when you touch the pin with the iron.These are very sentitive to static.

my supplier says they sell STK461, I will buy a replacement chip, remove the old one and see how i go. The old one has lots of pins, is the best way to remove it to snip the pins at the base then remove, then pull the pins out individually?